x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

resctrl is linux's defacto interface for managing cache and bandwidth
policies for groups of tasks.

To allow other architectures to make use of this pseudo filesystem,
move it live in /fs/resctrl instead of /arch/x86.

This move leaves behind the parts of resctrl that form the architecture
interface for x86.

Signed-off-by: James Morse <james.morse@arm.com>
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Discussion needed on how/when to merge this, as it would conflict with
all outstanding series. It's probably worth deferring to some opportune
time, but is included here for illustration.
11 files changed